by F. Kizito, E. Obuobie, J.P. Venot, C. Le Page and W. Daré Presented at the Final Volta Basin Development Challenge Science Workshop, September 2013

1. A Partner
of
Targeting interventions to reduce catchment
sedimentation: The case of a sub-watershed in the
White Volta Basin
Kizito F., Obuobie, E., Venot J.P.,
Le Page C., and Daré W

2. Andes • Ganges • Limpopo • Mekong • Nile • Volta
Presentation outline
1. Key message
2. Background and Purpose
3. Methodology
4. Findings
5. Lessons
6. Recommendations

3. Andes • Ganges • Limpopo • Mekong • Nile • Volta
Key message
- Study illustrates the relevance of
distributed erosion models to target erosion
control measures
- Illustrates the use of vegetative buffer strips
to reduce erosion rates by 10-20%
- Importance of community involvement

4. Andes • Ganges • Limpopo • Mekong • Nile • Volta
Background and Purpose
- Study area lies in the White Volta Basin
- Coverage of sub-basin is about 2,400 sq.km
- Major issues relate to climate
variability, poor soil functions, and reduced
storage capacity of reservoirs
- Intervention: landscape management to
reduce erosion and sedimentation

5. Andes • Ganges • Limpopo • Mekong • Nile • Volta
Background
%
%
%
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_
_
_
_
_
_ _
_ ___ _
__ __ __
_ __
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__ __ ___ _ ___ ___ _ __ _ _ __ __ __ __ ___ __ _____
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#*
#*
5
5
5
5
55
5
5
5
5Nangodi on Red Volta
Yarugu on White Volta
BANSI BAWKU
TILLI
BIDURI
BINABA
TIMONDE
KOSANABA
WIDENABA
NAFKULIGA
ZONGOYIRI
0°0'0"
0°0'0"
11°0'0"N 11°0'0"N
±
0 7 14 21 283.5
Kilometers
V4 Watershed
5 V4 Communities
White Volta Basin Boundary
_ Small reservoirs
#* Flow Stations
Rivers

6. Andes • Ganges • Limpopo • Mekong • Nile • Volta
Methodology
Hydrological modeling
Wet season Dry season
Participatory methods

7. Andes • Ganges • Limpopo • Mekong • Nile • Volta
Findings

8. Andes • Ganges • Limpopo • Mekong • Nile • Volta
Findings
0
200
400
600
800
1000
1200
1400
16000.00
100.00
200.00
300.00
400.00
500.00
600.00
1968 1973 1978 1983 1988 1993 1998 2003
Rainfall(mm)
Discharge(m3/s)
Rainfall Confidence band Observed Flow Simulated Flow

9. Andes • Ganges • Limpopo • Mekong • Nile • Volta
Findings
Major contribution:
Upstream catchments

10. Andes • Ganges • Limpopo • Mekong • Nile • Volta
Findings
- NE portion is most vulnerable
- Highly linked to landscape
attributes

11. Andes • Ganges • Limpopo • Mekong • Nile • Volta
Findings
- With vegetative buffers in place
- Erosion reduction by up to 15%

12. Andes • Ganges • Limpopo • Mekong • Nile • Volta
Recommendations
- Explore linkage with V1 on scaling out
interventions
- Targeted interventions are context specific
dependent on the biophysical
characteristics as well as social dimensions
- Intervention need to consider associated
environmental consequences, use of
ecosystem based approaches would be
appropriate